The invention relates to the field of making semiconductor components or elements, in particular on the basis of components or elements of the silicon on insulator (SOI) type.
A SOI structure comprises a layer of silicon having components properly formed therein, and beneath which is an insulator layer, for example of silicon dioxide, is buried. This layer provides insulation against parasitic currents and charges coming from ionized particles. It also provides good insulation from adjacent components made in the same layer of silicon, and in particular it provides a significant decrease in parasitic capacitances between such adjacent components. The insulating layer in turn rests on a substrate of silicon which acts as a mechanical support.
In certain cases or in certain applications, it is desirable to make one or more cavities in a silicon substrate or in a semiconductor material. The term “cavity” is used herein to mean an empty volume covered by or located within a layer of semiconductor material.
At present there is also a need for components or elements or structures that include such cavities. The present invention now satisfies this need.